Romex for HVAC compressor?

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Ima

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Hi all,
I have recently seen an installation of a new mini-split HVAC system where a compressor was installed on a pad outdoors next to the house. Insulated refrigerant pipes and 14-3 NM-B wire run from two locations on the second floor, and one on the third floor. These are covered by vertical metal channels screwed to the siding which run from the origins on the second and third floors to about one foot above ground.

At the bottom of these channels, the insulated pipes and wire run to the compressor unit with no protection from the weather. One of these channels is about 10 feet from the compressor, and the other two are within two feet.

Being clearly unacceptable, the homeowner notified the HVAC installer. The HVAC installer offered to run Seal-tite over the NM-B wiring extending out of the vertical channels to the compressor. Would this be safe and up to code?

I had thought that it wouldn't, based on 334.12(B) and the NM-B within the channels. I think the best solution is to replace these runs of wire with UF-B. Does that make sense?

Thanks!
 
Ima said:
14-3 NM-B wire run from two locations on the second floor, and one on the third floor. These are covered by vertical metal channels screwed to the siding which run from the origins on the second and third floors to about one foot above ground.

Would this be safe and up to code?
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Safe, maybe, up to code, no. Clearly a damp location.

334.12(B) Types NM and NMS. Types NM and NMS cables shall not be used under the following conditions or in the following locations:

(1) Where exposed to corrosive fumes or vapors

(2) Where embedded in masonry, concrete, adobe, fill, or plaster

(3) In a shallow chase in masonry, concrete, or adobe and covered with plaster, adobe, or similar finish

(4) In wet or damp locations
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The HVAC installer offered to run Seal-tite over the NM-B wiring extending out of the vertical channels to the compressor. Would this be safe and up to code?
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Safe, yes. Compliant, no.


If the installation was done like this in the first place, he wouldn't have had a problem with the HO.

Short runs of NM like this are sleeved outdoors all the time but it is not code compliant. I believe it was made crystal clear in 2005.

Technical foul in my humble opinion.
 
NM is not permitted outside in damp or wet locations. UF allowed and then might need protection from damage. Was a permit pulled ? Was the guy licensed to do electrical ?
 
Up to code? No. Done all the time? yes. Depends on who's looking. Check your area and see what they are getting away with??? It's your ticket. To be code, bring the romes to a wp jbox or disconect and change over to THhn/thwn and run sealtite or carflex.
 
Thanks everyone for your helpful replies :) I think I understand it much better now.

K8MHZ said:
The other thing is that the location doesn't change based upon the conduit.

If NM-B is not allowed in a certain area or application putting it into flexible conduit won't change that issue.
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I thought this was the case. Could you possibly point me towards the section of the 2005 NEC where it's spelled out?


220/221 said:
Safe, yes. Compliant, no.


If the installation was done like this in the first place, he wouldn't have had a problem with the HO.

Short runs of NM like this are sleeved outdoors all the time but it is not code compliant. I believe it was made crystal clear in 2005.

Technical foul in my humble opinion.
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I agree with this. I too think that if it had looked better, it would have never been questioned.


Jim W in Tampa said:
NM is not permitted outside in damp or wet locations. UF allowed and then might need protection from damage. Was a permit pulled ? Was the guy licensed to do electrical ?
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I haven't heard of a permit so I would guess not, but I will check. It certaintely seems that he shouldn't have been licensed at least, as he left an ungrounded junction box which wasn't secured in an indoor closet.

Thanks again everyone :)
 
Ima said:
...
I thought this was the case. Could you possibly point me towards the section of the 2005 NEC where it's spelled out? ...
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I don't think it was spelled out in the 2005 code. 300.9 was added to the 2008 code to make it clear that the inside of a conduit that is installed in a wet location is a wet location.
 
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